Awesome! Although that's ambitiously early. I feel like 40 minutes before doors is plenty. Although it is quite nice out today, so it shouldn't be too bad.
My main reason for getting there around 40-45 before doors is so I can get inside to get close to the stage; I try to do that at all shows I go to. But like you mentioned the show probably won't be sold out, so I could probably find my way to the front anyways, if I left a little later. The show at the Varsity back in 2009 was pretty packed though, so tonight should be even more packed, and more fun I think. Gah going to be such a good night.